4 files changed, 181 insertions, 1 deletions

diff --git a/include/linux/perf_counter.h b/include/linux/perf_counter.h
index a9d823a93fe8..8e6460fb4c02 100644
--- a/include/linux/perf_counter.h
+++ b/include/linux/perf_counter.h
@@ -734,6 +734,8 @@ extern int sysctl_perf_counter_mlock;
 extern int sysctl_perf_counter_sample_rate;
 
 extern void perf_counter_init(void);
+extern void perf_tpcounter_event(int event_id, u64 addr, u64 count,
+                                 void *record, int entry_size);
 
 #ifndef perf_misc_flags
 #define perf_misc_flags(regs)   (user_mode(regs) ? PERF_EVENT_MISC_USER : \
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index ce4b01c658eb..5541e75e140a 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -98,6 +98,53 @@ struct perf_counter_attr;
 #define __SC_TEST5(t5, a5, ...) __SC_TEST(t5); __SC_TEST4(__VA_ARGS__)
 #define __SC_TEST6(t6, a6, ...) __SC_TEST(t6); __SC_TEST5(__VA_ARGS__)
 
+#ifdef CONFIG_EVENT_PROFILE
+#define TRACE_SYS_ENTER_PROFILE(sname)                                         \
+static int prof_sysenter_enable_##sname(struct ftrace_event_call *event_call)  \
+{                                                                              \
+        int ret = 0;                                                           \
+        if (!atomic_inc_return(&event_enter_##sname.profile_count))            \
+                ret = reg_prof_syscall_enter("sys"#sname);                     \
+        return ret;                                                            \
+}                                                                              \
+                                                                               \
+static void prof_sysenter_disable_##sname(struct ftrace_event_call *event_call)\
+{                                                                              \
+        if (atomic_add_negative(-1, &event_enter_##sname.profile_count))       \
+                unreg_prof_syscall_enter("sys"#sname);                         \
+}
+
+#define TRACE_SYS_EXIT_PROFILE(sname)                                          \
+static int prof_sysexit_enable_##sname(struct ftrace_event_call *event_call)   \
+{                                                                              \
+        int ret = 0;                                                           \
+        if (!atomic_inc_return(&event_exit_##sname.profile_count))             \
+                ret = reg_prof_syscall_exit("sys"#sname);                      \
+        return ret;                                                            \
+}                                                                              \
+                                                                               \
+static void prof_sysexit_disable_##sname(struct ftrace_event_call *event_call) \
+{                                                                              \
+        if (atomic_add_negative(-1, &event_exit_##sname.profile_count))        \
+                unreg_prof_syscall_exit("sys"#sname);                          \
+}
+
+#define TRACE_SYS_ENTER_PROFILE_INIT(sname)                                    \
+        .profile_count = ATOMIC_INIT(-1),                                      \
+        .profile_enable = prof_sysenter_enable_##sname,                        \
+        .profile_disable = prof_sysenter_disable_##sname,
+
+#define TRACE_SYS_EXIT_PROFILE_INIT(sname)                                     \
+        .profile_count = ATOMIC_INIT(-1),                                      \
+        .profile_enable = prof_sysexit_enable_##sname,                         \
+        .profile_disable = prof_sysexit_disable_##sname,
+#else
+#define TRACE_SYS_ENTER_PROFILE(sname)
+#define TRACE_SYS_ENTER_PROFILE_INIT(sname)
+#define TRACE_SYS_EXIT_PROFILE(sname)
+#define TRACE_SYS_EXIT_PROFILE_INIT(sname)
+#endif
+
 #ifdef CONFIG_FTRACE_SYSCALLS
 #define __SC_STR_ADECL1(t, a)           #a
 #define __SC_STR_ADECL2(t, a, ...)      #a, __SC_STR_ADECL1(__VA_ARGS__)
@@ -113,7 +160,6 @@ struct perf_counter_attr;
 #define __SC_STR_TDECL5(t, a, ...)      #t, __SC_STR_TDECL4(__VA_ARGS__)
 #define __SC_STR_TDECL6(t, a, ...)      #t, __SC_STR_TDECL5(__VA_ARGS__)
 
-
 #define SYSCALL_TRACE_ENTER_EVENT(sname)                                \
         static struct ftrace_event_call event_enter_##sname;            \
         struct trace_event enter_syscall_print_##sname = {              \
@@ -134,6 +180,7 @@ struct perf_counter_attr;
                 init_preds(&event_enter_##sname);                       \
                 return 0;                                               \
         }                                                               \
+        TRACE_SYS_ENTER_PROFILE(sname);                                 \
         static struct ftrace_event_call __used                          \
           __attribute__((__aligned__(4)))                               \
           __attribute__((section("_ftrace_events")))                    \
@@ -145,6 +192,7 @@ struct perf_counter_attr;
                 .regfunc                = reg_event_syscall_enter,      \
                 .unregfunc              = unreg_event_syscall_enter,    \
                 .data                   = "sys"#sname,                  \
+                TRACE_SYS_ENTER_PROFILE_INIT(sname)                     \
         }
 
 #define SYSCALL_TRACE_EXIT_EVENT(sname)                                 \
@@ -167,6 +215,7 @@ struct perf_counter_attr;
                 init_preds(&event_exit_##sname);                        \
                 return 0;                                               \
         }                                                               \
+        TRACE_SYS_EXIT_PROFILE(sname);                                  \
         static struct ftrace_event_call __used                          \
           __attribute__((__aligned__(4)))                               \
           __attribute__((section("_ftrace_events")))                    \
@@ -178,6 +227,7 @@ struct perf_counter_attr;
                 .regfunc                = reg_event_syscall_exit,       \
                 .unregfunc              = unreg_event_syscall_exit,     \
                 .data                   = "sys"#sname,                  \
+                TRACE_SYS_EXIT_PROFILE_INIT(sname)                      \
         }
 
 #define SYSCALL_METADATA(sname, nb)                             \
diff --git a/include/trace/syscall.h b/include/trace/syscall.h
index df628404241a..3ab6dd18fa3a 100644
--- a/include/trace/syscall.h
+++ b/include/trace/syscall.h
@@ -58,5 +58,12 @@ extern void unreg_event_syscall_exit(void *ptr);
 enum print_line_t print_syscall_enter(struct trace_iterator *iter, int flags);
 enum print_line_t print_syscall_exit(struct trace_iterator *iter, int flags);
 #endif
+#ifdef CONFIG_EVENT_PROFILE
+int reg_prof_syscall_enter(char *name);
+void unreg_prof_syscall_enter(char *name);
+int reg_prof_syscall_exit(char *name);
+void unreg_prof_syscall_exit(char *name);
+
+#endif
 
 #endif /* _TRACE_SYSCALL_H */
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index e58a9c11ba85..f4eaec3d559a 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -1,6 +1,7 @@
 #include <trace/syscall.h>
 #include <linux/kernel.h>
 #include <linux/ftrace.h>
+#include <linux/perf_counter.h>
 #include <asm/syscall.h>
 
 #include "trace_output.h"
@@ -252,3 +253,123 @@ struct trace_event event_syscall_enter = {
 struct trace_event event_syscall_exit = {
         .trace                  = print_syscall_exit,
 };
+
+#ifdef CONFIG_EVENT_PROFILE
+static DECLARE_BITMAP(enabled_prof_enter_syscalls, FTRACE_SYSCALL_MAX);
+static DECLARE_BITMAP(enabled_prof_exit_syscalls, FTRACE_SYSCALL_MAX);
+static int sys_prof_refcount_enter;
+static int sys_prof_refcount_exit;
+
+static void prof_syscall_enter(struct pt_regs *regs, long id)
+{
+        struct syscall_metadata *sys_data;
+        int syscall_nr;
+
+        syscall_nr = syscall_get_nr(current, regs);
+        if (!test_bit(syscall_nr, enabled_prof_enter_syscalls))
+                return;
+
+        sys_data = syscall_nr_to_meta(syscall_nr);
+        if (!sys_data)
+                return;
+
+        perf_tpcounter_event(sys_data->enter_id, 0, 1, NULL, 0);
+}
+
+int reg_prof_syscall_enter(char *name)
+{
+        int ret = 0;
+        int num;
+
+        num = syscall_name_to_nr(name);
+        if (num < 0 || num >= FTRACE_SYSCALL_MAX)
+                return -ENOSYS;
+
+        mutex_lock(&syscall_trace_lock);
+        if (!sys_prof_refcount_enter)
+                ret = register_trace_syscall_enter(prof_syscall_enter);
+        if (ret) {
+                pr_info("event trace: Could not activate"
+                                "syscall entry trace point");
+        } else {
+                set_bit(num, enabled_prof_enter_syscalls);
+                sys_prof_refcount_enter++;
+        }
+        mutex_unlock(&syscall_trace_lock);
+        return ret;
+}
+
+void unreg_prof_syscall_enter(char *name)
+{
+        int num;
+
+        num = syscall_name_to_nr(name);
+        if (num < 0 || num >= FTRACE_SYSCALL_MAX)
+                return;
+
+        mutex_lock(&syscall_trace_lock);
+        sys_prof_refcount_enter--;
+        clear_bit(num, enabled_prof_enter_syscalls);
+        if (!sys_prof_refcount_enter)
+                unregister_trace_syscall_enter(prof_syscall_enter);
+        mutex_unlock(&syscall_trace_lock);
+}
+
+static void prof_syscall_exit(struct pt_regs *regs, long ret)
+{
+        struct syscall_metadata *sys_data;
+        int syscall_nr;
+
+        syscall_nr = syscall_get_nr(current, regs);
+        if (!test_bit(syscall_nr, enabled_prof_exit_syscalls))
+                return;
+
+        sys_data = syscall_nr_to_meta(syscall_nr);
+        if (!sys_data)
+                return;
+
+        perf_tpcounter_event(sys_data->exit_id, 0, 1, NULL, 0);
+}
+
+int reg_prof_syscall_exit(char *name)
+{
+        int ret = 0;
+        int num;
+
+        num = syscall_name_to_nr(name);
+        if (num < 0 || num >= FTRACE_SYSCALL_MAX)
+                return -ENOSYS;
+
+        mutex_lock(&syscall_trace_lock);
+        if (!sys_prof_refcount_exit)
+                ret = register_trace_syscall_exit(prof_syscall_exit);
+        if (ret) {
+                pr_info("event trace: Could not activate"
+                                "syscall entry trace point");
+        } else {
+                set_bit(num, enabled_prof_exit_syscalls);
+                sys_prof_refcount_exit++;
+        }
+        mutex_unlock(&syscall_trace_lock);
+        return ret;
+}
+
+void unreg_prof_syscall_exit(char *name)
+{
+        int num;
+
+        num = syscall_name_to_nr(name);
+        if (num < 0 || num >= FTRACE_SYSCALL_MAX)
+                return;
+
+        mutex_lock(&syscall_trace_lock);
+        sys_prof_refcount_exit--;
+        clear_bit(num, enabled_prof_exit_syscalls);
+        if (!sys_prof_refcount_exit)
+                unregister_trace_syscall_exit(prof_syscall_exit);
+        mutex_unlock(&syscall_trace_lock);
+}
+
+#endif
+
+